Return-Path: bfields@fieldses.org
Date: Wed, 12 Nov 2014 15:07:02 -0500
To: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Steve Dickson <SteveD@redhat.com>, Chuck Lever <chuck.lever@oracle.com>,
        Benjamin Coddington <bcodding@redhat.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: mount default minor version behavior
Message-ID: <20141112200702.GA8790@fieldses.org>
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From: "J. Bruce Fields" <bfields@fieldses.org>
List-ID: <linux-nfs.vger.kernel.org>

On Wed, Nov 12, 2014 at 01:41:03PM -0500, Trond Myklebust wrote:
> The NFS client modules are loaded on demand. The kernel will therefore
> not actually know the capabilities until we attempt the mount.

Right, but the main nfs module can know at least an upper bound, and
that's all mount needs to start negotiation, isn't it?  If the kernel
thinks 4.99 is supported but in fact that module turns out to be
blacklisted or something, then we can always try it and fall back.

--b.